Actually a horizontal shaft motor with a mule drive will lose approx 5hp due to the belts having to make the 90degree turn. There have been some manufacturers that backed that data up with dyno numbers. I don't remember where I saw the data but it does stand to reason that with a vert shaft motor you don't have to pull your belts through a bend and pulleys. You will also wear and heat up a belt faster with each 90degree bend you have.

The big advantage to the horizontal shaft engine is the engine life and quality. The power is virtually the same for both types of engines, so the decision to go horizontal is a smart one as it will save you repair money over the life of the machine.

NCPELICAN.....I don't want to get into a dabate but the statement about horizontal lasting longer and being cheaper over the life of the machine isn't true. In todays age with tech advances in engine designs a Kawasaki vert and horiz shaft motors are of the same quality and use pretty much the same parts. I have seen Kaw 25hp motors with over 4000hours on them. If you take care of them they will all last.

I think the horizontal shaft motor has two advantages, the deck can be raised higher generaly 5 inches as opposed to 4 inches for vertical shaft motor and when going down a slope its easier to turn the mower. Thats just my opinion.

So the consensus seems to be go with a horizontal shaft engine setup? I do agree with the concept of keeping the clutch up higher but the belt(s) having to make 90* bends does seem to be a concern for some people.

IMHO - both are fine, as said before MAINTENANCE is the key to longevity of either engine. You might want to wonder WHY horizontal or vertical instead, the vert engines are mostly found in the 'compact' style Z's and the horizontal engines are mostly in the 'full size' machines. I use the compact style machine for MY lawns as they are rather tightly landscaped and the 52" deck will still cover a lot of ground on the few accounts that I have that are 'wide open'. If you desire 'liquid cooling', 'fuel injection' or 'diesel' then you will be purchasing a horizontally mounted engine as these options are not available in the vertical style YET.